The use of asphalt for roofing products such as shingles and built up roofing is well known. In order to extend the asphalt and provide reinforcement, these products, as well as other asphalt products, contain glass fiber reinforcements and mineral fillers. Other asphalt products include laminating asphalt, crack fillers, mastics and adhesives.
The preferential asphalt for such products is a coating grade asphalt or a good quality roofing flux having a softening point above about 105.degree. C. and a penetration at 25.degree. C. between about 17-22.
In order to reduce costs, however, harder asphalt fluxes such as paving grade asphalt must be used. This requires the use of asphalt modifiers to make the hard fluxes process easily and perform well in the asphalt products.
One known asphalt modifier which provides good results when blended with hard fluxes is an amide wax, as taught in U.S. Pat. No. 4,554,023 to Janicki. This modifier increases the softening point of the asphalt, while lowering the viscosity of the asphalt at elevated processing temperatures. Amide wax synthesis involves a condensation reaction where fatty acid and diamine are reacted together to form an amide wax and water.
A problem with the specific wax asphalt modifiers taught in the prior art, however, is their high relative cost. There is a need for lower cost asphalt modifiers which can increase the softening point of the asphalt while still giving low viscosity at processing temperatures.